Remove runtime flags for Proxy and Reflect

test/mjsunit/regress/regress-crbug-506956.js

Index: test/mjsunit/regress/regress-crbug-506956.js
diff --git a/test/mjsunit/regress/regress-crbug-506956.js b/test/mjsunit/regress/regress-crbug-506956.js
index 73eb2f2220b6dbff80ea93bf35af4d1af1699508..8bca70803fb0d52f99e137ae7b78ccbc0035581f 100644
--- a/test/mjsunit/regress/regress-crbug-506956.js
+++ b/test/mjsunit/regress/regress-crbug-506956.js
@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// Flags: --harmony-proxies
-
 try {
   var p = new Proxy({}, {
       getPropertyDescriptor: function() { throw "boom"; }